Walking on two legs is inherently unstable. Still, we humans perform remarkable well at it, mostly without falling. To gain more understanding of the role of the brain in controlling gait stability we measured brain activity using electro-encephalography (EEG) during stabilized and normal walking. Subjects walked on a treadmill in two conditions, each lasting 10 min; normal, and while being lat...

In order to evaluate the EEG of patients with epilepsy, chaos analysis was performed for the subdural EEG time series data. The chaos attractor was reconstructed in the phase space and the correlation dimension. KS entropy calculated from the Lyapunov exponents was evaluated. Before the seizure attack, the KS entropy showed a lower value when compared with the time series data recorded during h...

The problem of determining a continuously distributed neuronal current inside the brain under the assumption of a three-shell model is analysed. It is shown that for an arbitrary geometry, electroencephalography (EEG) provides information about one of the three functions specifying the three components of the current, whereas magnetoencephalography (MEG) provides information about a combination...

Cerebrospinal fluid pressure was measured in twenty-three patients undergoing encephalography. Three different programmes were followed to determine the effect of nitrous oxide on intracranial pressure with and without injection of air and nitrous oxide into the theca. In every case the initial c.s.f. pressure remained unchanged when nitrous oxide was used for encephalography, while it increase...

SEIZURES induced by cardiazol (pentamethylene tetrazol) are not identical with Grand Mal, but the clinical resemblance is sufficiently close to justify their study by electro-encephalography. Gibbs, Gibbs, and Lennox (1937) have shown conclusively that a genuine epileptic fit is accompanied by a rhythmic, high-potential electrical discharge from the cortex, and Golla, Graham, and Walter (1937) ...

BACKGROUND Interpreting and controlling bioelectromagnetic phenomena require realistic physiological models and accurate numerical solvers. A semi-realistic model often used in practise is the piecewise constant conductivity model, for which only the interfaces have to be meshed. This simplified model makes it possible to use Boundary Element Methods. Unfortunately, most Boundary Element soluti...

Localizing the generators of epileptic activity in the brain using Electro-EncephaloGraphy (EEG) or Magneto-EncephaloGraphy (MEG) signals is of particular interest during the pre-surgical investigation of epilepsy. Epileptic discharges can be detectable from background brain activity, provided they are associated with spatially extended generators. Using realistic simulations of epileptic activ...

OBJECTIVE To compare the localizations of different neural sources (a) obtained from intracerebral evoked responses and (b) calculated from surface auditory evoked field responses recorded in the same subjects. Our aim was to evaluate the resolving power of a source localization method currently used in our laboratory, which is based on a recent spatio-temporal algorithm used in magneto-encepha...

Air encephalography in the absence of a spaceoccupying lesion of the brain is usually a harmless but unpleasant investigation that is necessary in the differential diagnosis of organic dementias and neurological syndromes of uncertain origin. It is known that subdural effusions may follow encephalography in children (Smith and Crothers, 1950). The development of a subdural haematoma in an adult...